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The preservation of trees within construction activities is frequently dependent on accurate information on root location within the soil profile.

All excavation in the presence of tree roots is injurious to some extent so it is generally the case to limit the injury to the tree roots rather than avoiding it altogether.

Greenwood Consulting provides root zone investigation using the following methodologies:

1) Compressed air excavation

The least injurious of the 3 mechanisms is compressed air excavation. It is most useful with reasonably friable soils such as those found in Bayside areas. It is suitable for removing topsoil to a depth of 150m.



2) Hydro excavation

Hydro excavation is the next most injurious. Even when used carefully by competent and experienced operators,  as soon as the high-pressure water touches the root, it removes the bark and cambium from that section of the root. The cambium is the actual living tissue in the wood, found immediately underneath the bark. It is where the cell generation and multiplication take place and is vital for the health of the tree.


Hydro excavation is the best choice for rocky, heavy, clay soils.

3) Hand excavation

Of the 3 methods of excavation, hand excavation is often the most injurious.  By the time you find the tree root with your spade, mattock or pick you have done the root so much damage that a large segment of the root, if not the entire root, is likely to die.

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